Microphone



Oct. 16, 1934. A, CQMSTOCK 1,976,835

MICROPHONE Filed July 50, 1932 INVENTOR -f0mes A. COIDS/OCK ATTORNEYS screws or in any other suitable manner.

Patented Oct. 16, 1934 1,976,835 MICROPHONE James A. Comstock, Cleveland, Ohio, assignor to -WonderSpecialties, Inc:., Clev ela'nd, Ohio' 1 Applicationduly so, 1932, seal No. 626,261 i 1 clai (01. 179-421) This invention relates to the art of micro.- phones which are adapted for: use in' connection with a radio receiving set. 1 r v 1 There haspreviously been devised the combination of'sa'radio receiving system with its usual amplifying means, and .a. microphone which. can be substituted in the system, at the will of the operator; for theradio receiving set, whereby there-is permitted the enjoyment and amusement of local transmission-and broadcasting in the home or elsewhere. With this combined'system, the same amplifying and broadcasting devices can be employed with either the radio receiving setnor the local microphone, the interchangefrom the one to the other being efiectedby means of 'a switch. .Itis-this combined system to .whichmypres ent invention relates, and the object-pf the, presentinvention' is to devise an improved form and construction ohmicrophonewhichcan be,

mariufacturedand soldiat'. a comparatively low cost and readily installed by the user in the radio system.

More specifically, my object is to devise such 51a microphone of miniature size, the parts of which can be manufactured largely in the form of sheet metal stampings and which presents a decidely attractive appearance.

Other objects will appear from the following 3 .1 description and claims when considered together with the accompanying drawing.

Fig. 1 is a front elevation of my improved form of miniature or toy microphone.

Fig. 2 is a view taken on line 22 of Fig. 1; 3. and

Fig. 3 is a view taken on line 3-3 of Fig. 2. It is to be understood that the present disclosure is merely for purposes of illustration and that other modifications and variations may be 14 devised without departing from the spirit of .45; casing portion and a base portion upon which the upper casing is supported. Within the upper casing portion are enclosed the operative parts of the microphone itself, including the diaphragms and the carbon granules.

51),; The upper casing portion is constructed from two companion sheet metal stampings 1 and 2- which are of substantially the same shape and have their marginal flange portions secured together in overlapping relation by means of The front and rear-.metal 'stampings 1 and *2- are of substantially conical shape,and the front mem-, her 1 has a series of openings 3 through. thecentral parts thereof to permit transmission of soundtherethrough, while a plurality of annu-. lar ribs e are'formedin :the tapering part thereof for purposes of reinforcement as 1 well as artisticappearance. 1

The base portion consists principally of a single sheet metal stamping -5 of substantially 655: bell shape, the bottom of which is closed by an auxiliary sheet metal stamping 6 having an annular. flange frictional engagement with or otherwise suitably securedto the corresponding annular fiangeof the mainbase portion 5. 1"

The upper casing is welded'orotherwise secured-"to the base portion in a suitable manner.

:The large diaphragm 7:,is stamped from sheet tin, 'orother suitable metal andis secured in pa sition-within the upper casing by engagement Z5? around its edge portion between the. Bristol washers 8 which are positioned between the edge of the inner flange of the rear member 2 and the angle between the annular flange and the tapering of the front member 1. The edge of 8 the diaphragm is of slightly less diameter than the inside diameter of the flange on the front member 1, so that the diaphragm 7 is properly insulated by the washers 8 which are suitable for this purpose.

The small diaphragm 9 is also stamped from sheet tin, or other suitable metal, and is secured by means of a tack or in some other suitable manner to the round Wooden block 10 which in turn is screwed to the central part of the rear 901 member 2.

The space between the diaphragms 7 and 9 is just sufficient to accommodate the felt washer 11 and the carbon granules 12 which are placed within the felt washer, as indicated upon the drawing. The washer 11 may be glued or otherwise secured in position.

As indicated in the drawing, the small diaphragm 9 is of square form and has one corner extending below the edge of the block 10; and to the lower corner portion of the diaphragm 9 there is attached the one end of the electric wire 13. This wire 13 is suitably insulated and extends through an aperture 14 in the engaging portions of the upper casing and the base por- 9: tion. This wire 13 extends thence out through an insulated bushing 15 provided in an aperture in the rear part of the base portion. Likewise, another electric wire 16 extends through the same bushing 15 and has its inner end grounded 9 As a means of manually controlling the intro+:. j duction of this microphone into the combination,

with the radio amplifying system, I have provided the switch 18 which consistsof a. strip of spring metal riveted at 19 to the lower part of the front wall of the upper casing and having the finger button 20 of fibre attached near the other end thereof and extending through an aperture in the front wall 1 of the casing so as tobe adapted for manipulation by the operator for forcing the switch in closed position against the large diaphragm 7. v

Upon closing the. switch, the circuit will be closed through wire 16, the base and upper casing, the switch itself, the large-diaphragm 7, through the carbon granules 12 to the small diaphragm 9 and to the other wire 13. With the microphone included inthe circuit, and theradio receiving set eliminated, any local sounds entering the microphone willbe transmitted through the radio-amplifying system and thence broadcast from the loud speaker of the radio set so as to produce amusement, as will be understood by those who are familiar with the prior art herein referred to.

The particular form and manner of construction of the microphone herein disclosed possesses marked advantages from the standpoints of manufacture and artistic appearance. :By virtue of the stamping. process which may be employed in the manufacture of the parts of the microphone casing and base portions, as well as in the manufacture of the large and small diaphragms, the cost of production is reduced to a comparatively low point.

At the same time there is produced a form of device possessing a decidedly artistic appearance, especially since practically any desired style of finishniay be given to the entire sheet metal body of the microphone.

Furthermore, this microphone structure is decidedly sturdy and durable and nothing is apt to get out of order from handling either in ship- -ping or during actual use.

- .Also, this particular form of microphone is well adapted to be held in the hand of the user or to stand upon a table or other support while being used.

1 Other objects will be apparent to those who are skilled in the art to which this invention relates. w v,

What I claim is:

A microphone including a casing and a base uponwhich the casing is supported, the casing consisting of frontand rear portions each of substantially frusto-conical shape, a diaphragm located in substantially the middle plane between the front and rear walls of the casing, electrical connections'for the diaphragm, and a hand-operated switch for including or excluding the diaphragm in. circuit, said switch being mounted upon theinside of the lower part of the conicalarea of the front portion of the casing and extending downwardly with its free end in themore restricted space between the front Wall of the diaphragmso as to facilitate opening the switch and. whereby the switch can be conveniently operated by a finger of the same hand by which and while the operator supports the base ofthe microphone in his hand. i

JAMES A. COMSTOCK. 

